code: def test_sparse_input_pad_and_mask(self):
      input_data = tf.sparse.SparseTensor(
          indices=[[0, 0], [1, 2]], values=[1, 2], dense_shape=[3, 4]
      )
  
      expected_mask = np.array([True, True, False])
  
      output = ToDense(pad_value=-1, mask=True)(input_data)
      self.assertTrue(hasattr(output, "_keras_mask"))
      self.assertIsNot(output._keras_mask, None)
      self.assertAllEqual(
          tf.keras.backend.get_value(output._keras_mask), expected_mask
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import numpy
  import tensorflow
  from tensorflow.python.framework import test_util
  from tensorflow_text.python.keras.layers.todense import ToDense
label_desc: Use image node_id 3 for calling the SparseTensorsToDenseLayerTest obj's underlying member method code with example usage: obj.test_sparse_input_pad_and_mask() without return types